• PNF and Movement
• /
• v.17 no.2
• /
• pp.329-337
• /
• 2019

Purpose: Ultrasound imaging is commonly used to measure the pennation angle of human skeletal muscles in vivo. However, manual assessment of the pennation angle using ultrasound images is subjective and time-consuming and requires a high level of examiner skill. The architectural analysis of human skeletal muscles is thus challenging. Automated approaches using image processing techniques are therefore required to estimate the pennation angle in ultrasound images. The purpose of this study was thus to assess the intra-tester and inter-tester reliability and validity of the pennation angle using an automatic measurement program. Methods: Twenty-two healthy young adults (mean age = 22.55 years) with no medical history of neurological or musculoskeletal disorders voluntarily participated in this study. Ultrasound imaging was used to measure the pennation angle of the gastrocnemius muscle at rest. One examiner acquired images from all the participants. The intra-tester and inter-tester reliability were evaluated using the intraclass correlation coefficient (ICC) to estimate reliability. Validity was measured using Pearson's correlation coefficient. Results: The intra-rater reliability was excellent for the automatic pennation angle measuring program and the manual pennation angle assessment method (ICC>0.95). The inter-rater reliability was also excellent for both methods (ICC>0.93). All the correlation coefficients for the automatic pennation angle measuring program and the manual pennation angle assessment method were 0.79, which indicated a significantly positive correlation (p<0.05). Conclusion: Pennation angle measurement using the automatic pennation angle measuring program showed acceptable reliability and validity. This study therefore demonstrated that the automatic measuring program was able to automatically measure the pennation angle of skeletal muscles using ultrasound images, and thus made it easy to investigate skeletal muscle architecture.

• Journal of The Korean Society of Integrative Medicine
• /
• v.5 no.1
• /
• pp.75-83
• /
• 2017

Purpose : The parameters used in architectural analysis are muscle thickness, fascicle length, pennation angle, etc. Pennation angle is an important muscle characteristic that plays a significant role in determining a fascicle's force contribution to movement. Ultrasonography has been widely used to obtain the image for measurement of a pennation angle since it is non-invasive and real-time. However, manual assessment in ultrasonographic images is time-consuming and subjective, making it difficult for using in muscle function analysis. Thus, in this study, I proposed an automatic method to extract the pennation angle from the ultrasonographic images of gastrocnemius muscle. Method : The ultrasonographic image obtained from 10 healthy participants's gastrocnemius muscle using for developed automatic measuring program. Automatic measuring program algorithm consists with preprocessing, line detection, line classification, and angle calculation. The resulting image was then used to detect the fascicles and aponeuroses for calculating the pennation angle with the consideration of their distribution in ultrasonographic image. Result : The proposed automatic measurement program showed the stable repeatability of pennation angle calculation. Conclusion : This study demonstrated that the proposed method was able to automatically measure the pennation angle of gastrocnemius, which made it possible to easily and reliably investigate pennation angle more.

• Physical Therapy Korea
• /
• v.17 no.2
• /
• pp.43-50
• /
• 2010

The purpose of this study was to investigate the effects of Evjenth-Hamberg stretching on the active range of motion (ROM) of the hip joint and the pennation angle of the semitendinosus muscle. Eighty healthy adults participated in this study. The active ROM of the hip joint was measured by a goniometer and the pennation angle of the semitendinosus muscle was measured by ultrasonographic imaging (USI). Both ROM and pennation angle were recorded before and after the static stretching and the Evjenth-Hamberg stretching, respectively. Data were analyzed using paired t-lest and independent t-test at p<.05. The results were as follows: 1) The active ROM of the hip joint increased significantly after both stretching interventions compared with the baseline (p<.001). However, the active ROM of the hip joint increased significantly in Evjenth-Hamberg stretching compared with static stretching. 2) The pennation angle decreased significantly after both stretching interventions compared with the baseline (p<.001). However, the pennation angle decreased significantly in Evjenth-Hamberg stretching compared with static stretching. 3) Reliability data showed that there was a high consistency in USl measurements (ICC=.978). Our findings suggest that the Evjenth-Hamberg stretching was more effective than static stretching in increasing the active ROM of the hip joint and decreasing the pennation angle of the semitendinosus muscle.

• The Journal of Korean Physical Therapy
• /
• v.22 no.3
• /
• pp.55-59
• /
• 2010

Purpose: This study was designed to investigate the effect of a water exercise program on the pennation angle of the lower-limb muscle in women in their 20s. Methods: Ten female subjects were randomly divided into two groups, with 5 subjects exercising in water 0.7 m deep and 5 subjects exercising in water 1.4 m deep. They did the water exercising program for 40 minute per day, 3 days per week, for total 6 weeks. We measured the pennation angle of lower-limb muscle using ultrasonography. All measurements for each group were performed at pre-training and after 6 weeks of training. Results: The pennation angle was compared before and after the water exercise period for each group, and statistically significant changes within each group in measurements of the rectus femoris and tibialis anterior (p<0.05). However, there was no significant difference in muscle architecture by water depth (p>0.05) between the two groups. Conclusion: These results show that the pennation angle of the lower-limb muscle of women in their 20s changed after 6 weeks of participating in a water exercise program, but these changes were not dependent on the depth of the water in which the exercises were performed.

• Food Science of Animal Resources
• /
• v.40 no.6
• /
• pp.957-968
• /
• 2020

The influence of muscle architecture on muscle fiber characteristics and meat quality has not been fully elucidated. In the present study, muscle fiber characteristics on the chop surface of pork loin (M. longissimus thoracis et lumborum, LTL), pennation angle degree, and meat quality were evaluated to understand the pork LTL architecture and its relationship with the loin chop quality. Muscle fiber pennation degree ranged from 51.33° to 69.00°, resulting in an ellipse-shaped muscle fiber on the surface of pork loin chop. The cross-sectional area (CSA) on the sections cut vertical to the muscle length (M-Vertical) was considerably larger (p<0.05) than that on the sections cut vertical to the muscle fiber orientation (F-Vertical) regardless of the fiber type. Pennation angle is positively correlated with CSAs of F-Vertical (p<0.05) and with Warner-Bratzler shear force (r=0.53, p<0.01). Besides the shear force, lightness and pH were positively correlated with the fiber composition and CSA of IIX fiber (p<0.05); however, the redness, yellowness, drip loss, and cooking loss were not correlated with the pennation angle and muscle fiber characteristics on the chop surface (p>0.05). These observations might help us in better understanding pork loin architecture and the relationship between the pennation angle, muscle fiber characteristics, and meat quality of pork loin chop.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.26 no.1
• /
• pp.37-46
• /
• 2020

Background: The present study aimed to investigate the immediate effects of Soft Tissue Mobilization (STM) before Mobilization with Movement (MWM) on ankle ROM, pennation angle, balance in stroke patients. Methods: A total of 22 subjects were randomly assigned to one of two groups: the experimental group and the control group. The experimental group received intervention STM before MWM. STM was applied for one minute, MWM was applied one set of six times, in a total 3 sets. The passive ankle joint range of motion (ROM) was measured using a goniometer, the pennation angle was measured using RUSI, and the balance was measured using Timed Up & Go Test. Results: The ROM of the ankle dorsi-flexion, muscle tissue (pennation angle) and balance were significantly increased. Conclusion: In this study, it was confirmed that the ankle dorsi-flexion ROM, pennation angle of the medial gastrocnemius muscle, and balance were significantly improved in the group where STM was performed before the MWM intervention. Therefore, the physiotherapists should consider these results in their intervention. If MWM is applied to stroke patients, applying STM first is a better intervention.

• The Journal of the Society of Stroke on Korean Medicine
• /
• v.14 no.1
• /
• pp.102-106
• /
• 2013

■ Objectives The purpose of the this study was to investigate organization change(pennation angle) of lower extremity muscle in elderly with knee osteoarthritis through ultrasonic image. Also, we examined organizational change of muscle was by influenced after total knee replacement(TKR). ■ Methods Rectus femoris image was taken at 50% of the distance between the anterior superior iliac spine and the superior border of the patella. Vastus medialis image was taken at the most distal insertion level of vastus medialis on the medial border of the patella. measurements included the most distal insertion level of the vastus medialis on the medial border of the patella. ■ Results Change of pennation angle in rectus femoris showed decrease from 5.11° in preoperation to 4.29° in 1 week after operation. Change of pennation angle in vastus medialis showed decrease from 6.94° in preoperation to 5.76° in 1 week after operation. ■ Conclusion We consider decrease of pennation angle after total knee replacement in this study was casued by organizational change of muscle and this pennation angle was influenced force created by muscle. Therefore, we thinks that this pennation angle through ultrasonic image will be available to plane individual muscle exercise program and to confirm muscle mass by muscle strength training.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.12
• /
• pp.8684-8690
• /
• 2015

This study aimed to investigate the influence of the ankle dorsiflexion angle ($0^{\circ}$, $10^{\circ}$, and $20^{\circ}$) on the effectiveness of gastrocnemius stretching angle. The subjects of this study were 25 young man and female women. In all participants, the pennation angle of the medial head of the gastrocnemius was evaluated using ultrasonography at an ankle dorsiflexion angle of $0^{\circ}$, $10^{\circ}$, or $20^{\circ}$. Repeated measures analysis of variance was uesd to test for differences between ankle dorsiflexion angles. The independent t-test was performed to determine the significance of sex differences. The results of this study showed that the gastrocnemius pennation angle decreased as the ankle dorsiflexion angle increased, with significant interaction between each angle of ankle dorsiflexion angle (p<0.01). Sex comparison showed that the pennation angle was greater in man than in women, but the difference was not significant (p>0.05). According to the sex the gastrocnemius pennation angle is decreased as the ankle dorsiflexion angle increased (p<0.01). These results suggest that the end range of dorsiflexion is more beneficial for gastrocnemius stretching than a small range. Further studies are needed to investigate the influence of other factors, such as stretching angle and application time, on gastrocnemius stretching.

• The Journal of Korean Physical Therapy
• /
• v.19 no.2
• /
• pp.11-19
• /
• 2007

Purpose: The purpose of this study were to analyze ultrasonography on both sides of gastrocnemius medialis of stroke patient. Methods: In fourteen subjects with stroke, the gastrocnemius medialis(GM) muscle were scanned with ultrasonography at the muscle belly at rest at ankle angles of 0 degree (neutral position) and it were measured with ultrasonography on both sides of the leg. Muscle architecture (thickness, pennation angle, fascicle length, density, white area index) was examined using real-time B-mode ultrasonography with 7.5MHz linear-array prob. Results: Thickness of non-paratic side was significantly thicker than paratic side. Pennation angle of non-paratic side was significantly larger than paratic side. Fascicle length of non-para tic side was significantly smaller than paratic side. Density of non-paratic side was significantly smaller than paratic side. White area index of non-paranc side was significantly smaller than paratic side. Conclusion: This study showed that stroke have influenced on mechanical properties and quality properties of skeletal muscle architecture.

• Physical Therapy Rehabilitation Science
• /
• v.5 no.2
• /
• pp.89-94
• /
• 2016

Objective: This study was aimed to compare the thickness and pennation angle of gastrocnemius through ultrasonography during the heel-drop exercise on ankle dorsiflexion angle. Design: Cross-sectional study. Methods: Nineteen normal adults in their 20s had voluntarily participated in this study. All subjects performed the ankle heel-drop exercise with ankle dorsiflexed to $0^{\circ}$, $10^{\circ}$, and $20^{\circ}$: heel-drop exercise with ankle dorsiflexed to $0^{\circ}$ was executed on floor-level, heel-drop exercise with ankle dorsiflexed to $10^{\circ}$ on a wooden-block of 2.3 cm in height, and heel-drop exercise with ankle dorsiflexed to $20^{\circ}$ on a wooden-block of 5.5 cm in height. In each regimen, the subjects completed a session of 100 heel-drop exercises (10 repetitions${\times}$10 sets; with 30 seconds rest following each set; with 24 hours rest following each exercise). Before and immediately after each heel-drop exercise, the thickness and pennation angle of gastrocnemius were measured using an ultrasonography. Results: After the performance of the heel drop exercises with ankle dorsiflexed to $0^{\circ}$, $10^{\circ}$, and $20^{\circ}$, the thickness of the gastrocnemius was significantly higher than pre-exercise (p<0.05), and furthermore heel-drop exercise with ankle dorsiflexed to $10^{\circ}$ was significantly higher than exercise with the ankle dorsiflexed to $0^{\circ}$ (p<0.05). However, as for the pennation angle of the gastrocnemius, there were no significant changes after each heel-drop exercise. Conclusions: This finding suggest that the heel-drop exercise with ankle dorsiflexed to $0^{\circ}$, $10^{\circ}$, and $20^{\circ}$ is effective on the strengthening of the gastrocnemius. Furthermore, the heel-drop exercise with the ankle dorsiflexed to $10^{\circ}$ is more effective than with the ankle dorsiflexed to $0^{\circ}$.